Passive Continuous Cooling System for Spent Fuel Pool in Underground Nuclear Power Plant

Abstract

The invention discloses a passive continuous cooling system for a spent fuel pool of an underground nuclear power plant, which includes a spent fuel pool located in an underground cavern. The spent fuel pool is filled with cooling water, and the cooling water submerges the spent fuel assembly. It also includes closed ends, The inner cavity is filled with the cooling heat pipe of the working solvent. The lower end of the cooling heat pipe is a heat absorbing end and the upper end is a condensation end. The heat absorption end is immersed in cooling water, and the condensation end extends into the rock body. The invention adopts the passive design concept, realizes the cooling process of the spent fuel pool through natural physical processes such as liquid heating, evaporation, heat absorption, condensation heat release, and gravity reflux, without additional external power supply, so there is no spent fuel caused by the loss of cooling power Potential hazards of pool cooling water drying up and spent fuel burnout. The hierarchical arrangement of cooling heat pipes and accident emergency heat pipes ensures that there is no risk of radioactive leakage in the safe operation of the spent fuel pool and in the event of an accident.

Description

technical field [0001] The invention relates to nuclear power technology, in particular to a passive continuous cooling system for spent fuel pools in underground nuclear power plants. Background technique [0002] With the operation of nuclear power plants, the burnup of the loaded fuel continues to deepen. When the burnup depth reaches the design discharge burnup, the used nuclear fuel assemblies must be unloaded from the reactor. These unloaded nuclear fuels are spent fuel. Although the spent fuel cannot continue to maintain the chain nuclear reaction, it contains a large amount of radioactive elements, which will continuously emit a large amount of decay heat. Nuclear power plants typically store spent fuel in spent fuel pools filled with water for a year or more to keep it cool. At the same time, a forced water-cooled heat exchanger is used in the spent fuel pool to continuously export the decay heat out of the spent fuel pool to prevent the burning of the fuel claddin...

AI Technical Summary

Problems solved by technology

This design may lose the external power supply under accident conditions. The cooling water in the spent fuel pool is continuously evaporated under the action of decay heat. When the spent fuel is exposed to the water surface, the accumulated decay heat will burn the fuel cladding. Leaks that cause radioactivity, such as the radioactive leak from the spent fuel pool in the Fukushima nuclear accident in Japan in 2011

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